1. Field of the Invention
The present invention relates to a vehicle fuel tank which is made of a resin and is configured to suppress a flowing noise that is generated when fuel is caused to flow abruptly and violently in association with acceleration or deceleration of a vehicle.
2. Description of the Background Art
As vehicle fuel tanks, resin fuel tanks which are made by making use of blow molding have been put to practical use.
Vehicle fuel tanks which are put to a practical use have been considered to be sufficient from the viewpoint of practical use as long as they are molded to sizes which can store predetermined volumes of fuel.
As vehicle fuel tanks of this kind, there have been known vehicle fuel tanks in which a suppressor wall (a wave canceling plate) is provided at the time of molding to prevent the flow of fuel within the tank when a vehicle is accelerated or decelerated (refer, for example, Japanese Utility Model Unexamined Publication JP-UM-A-2-34443, page 1, FIG. 1 and Japanese Utility Model Examined Publication JP-UM-B-57-32909, page 2, FIG. 1).
FIG. 18 is a drawing which describes a first basic configuration of the conventional fuel tanks and is actually a front sectional view of a vehicle fuel tank 300 in which a suppressor wall 303 is formed as a separate member.
The vehicle fuel tank 300 is such as to be made up of a tank main body 301 which stores fuel and a suppressor wall (a wave canceling plate) 303. The suppressor wall is provided within the tank main body 301 to suppress the abrupt and violent flow of fuel 302 which would otherwise occur in association with acceleration or deceleration of a vehicle. Pluralities of through holes 304 are formed in the suppressor wall 303 for allowing the passage of the fuel 302. The suppressor wall 303 is formed separately from the tank main body 301. Also, the suppressor wall 303 is inserted in the tank main body 301 when the tank main body 301 is blow molded and is welded to the tank main body 301 after the blow molding.
In the vehicle fuel tank 300, however, the suppressor wall 303 is such as to be made to intersect with the longitudinal direction of the vehicle at right angles, and hence there is caused a drawback that the suppressing effect is small relative to a planar flow (a circular current) of the fuel that occurs within the vehicle fuel tank 300 when the vehicle is stopped or started drastically.
FIG. 19 is a drawing which describes a second basic configuration of the conventional fuel tanks and is actually a front sectional view of a vehicle fuel tank 310 in which suppressor walls 311 are formed separately.
The vehicle fuel tank 310 is such as to be made up of a tank main body 311 which stores fuel and suppressor walls (wave canceling plates) 313, 313 which are integrally provided within the tank main body 311. The suppressor walls 313 are formed integrally at two locations within the tank main body 311 by forming pairs of suppressor wall pieces 314, 315 from the top and bottom of the tank main body 311 at those two locations when the tank main body 311 is blow molded, so that an abrupt and violent flow of fuel 312 is suppressed which would otherwise occur in association with acceleration or deceleration of the vehicle.
In the vehicle fuel tank 310, however, as with the vehicle fuel tank 300 (refer to FIG. 13), the suppressor walls 313 are such as to be made to intersect with the longitudinal direction of the vehicle at right angles, and hence there is included a drawback that the suppressing effect is small relative to a planar flow (circular current) of the fuel that occurs within the vehicle fuel tank when the vehicle is stopped or started drastically.
Namely, a vehicle fuel tank is desired which can solve the drawback that the suppressing effect is small relative to the planar flow (circular current) of the fuel that occurs within the vehicle fuel tank when the vehicle is stopped or started drastically so as to provide a suppressing effect on the planar flow (circular current) of fuel.